The details of parametric tissue surrounding uterine cervix is incompletely visualized by the usual ultrasonic examination of female pelvic tissue with an abdominal compound contact scanner or a real-time electronic scanner, though the detection of cancer infiltration to the parametrium is important in the diagnosis of uterine cervical malignancy. The parametrium had been clinically examined by rectal manual palpation, though the results were insatisfactory. From the view points, an improved 3.5 MHz radial scan device and a pistol style high speed 5 MHz radial scanner were utilized in the present study on parametric cancer infiltration.
Fourty four parametria in 22 uterine cervical cancer patients were analyzed in the comparison of manual examination and ultrasonographic findings. Increased density of the echo, which was revealed by the accumulation of echo patterns, and directional multiplicity of the echo, which was detected by multiple and random distribution of the echo in the pattern, indicated true diagnosis of parametric cancer infiltration, since simple high brightness was related to inflamatory change in the parametrium as well as cancer infiltration, and negative cancer infiltration was accurately diagnosed with the correct parameters on ultrasonic radial scan images. In conclusion, the transrectal ultrasonic radial scan technique is statistically superior to the conventional manual palpation method.